extranodal involvement in lymphoma – a pictorial essay and retrospective analysis of 281 pet/ct studies

objective(s): the aim of this study is to evaluate the role of pet-ct in identification of different patterns of extranodal involvement in hodgkin’s disease (hd) and non-hodgkin’s lymphoma (nhl) and to enlist the common sites of extranodal involvement in each histological type and compare our results with the existing literature. methods: in this retrospective study of 281 cases of lymphomas of various histologies, we illustrate the spectrum of pet/ct features of extranodal lymphoma (enl) of commonly involved organs and compare our result with the literature. result: extranodal appearance in lymphoma is strikingly varied. diffuse large b cell lymphoma (dlbcl) is the commonest histological subtype and gastrointestinal tract is the commonest anatomical subsite in nhl. skeletal system is the commonest site for involvement in hd. conclusion: a broad spectrum of extranodal organs is involved in various subtype of lymphoma which can be depicted in pet-ct in the most appropriate manner. familiarity with the pattern of involvement is essential for comprehensive management.